Xtreme Energy XR258HR-12, Chevy Small Block
Hydraulic Roller-For throttle body 305 or 350, very good economy and power.
- Grind Number: XR258HR
- Lifter Type: Hydraulic Roller Lifter
- Engine Family: Chevrolet 262-400 c.i. 8 cyl. 1955-1998
- Cam Family: XTREME EnergyT Computer Controlled 1987-1998 305-350 Originally Equipped With Hydraulic Roller Camshaft, Except LT1 and LT4.
| Specifications | Intake | Exhaust | ||
| RPM Range: | Valve Lash: | |||
| Valve Timing: | Duration: | |||
| Lobe Separation: | Duration @ .050" Lift: | |||
| Intake Centerline: | Valve Lift: | |||
| Lobe Lift: | ||||
| Valve Timing @ 0.006 Lift: | ||||
Vehicle Fitments:
| Year | Make | Model | Submodel |
|---|---|---|---|
| 1987 - 1991 | Avanti | II | Base |
| 1991 - 1996 | Buick | Commercial Chassis | Base |
| 1991 - 1993 | Buick | Roadmaster | Estate Wagon |
| 1992 - 1993 | Buick | Roadmaster | Limited, Base |
| 1990 - 1992 | Cadillac | Brougham | Base, d'Elegance |
| 1992 - 1996 | Cadillac | Commercial Chassis | Base, Brougham |
| 1993 | Cadillac | Fleetwood | Base, Brougham |
| 1994 | Chevrolet | Blazer | Base, Silverado Sport |
| 1992 - 1993 | Chevrolet | Blazer | Cheyenne |
| 1987 | Chevrolet | Blazer | Custom Deluxe |
| 1991 - 1994 | Chevrolet | Blazer | Nevada |
| 1988 - 1991 | Chevrolet | Blazer | Scottsdale |
| 1987 - 1994 | Chevrolet | Blazer | Silverado |
| 1990 - 1993 | Chevrolet | C1500 | 454 SS |
| 1989 - 1995 | Chevrolet | C1500 | Base |
| 1988 - 1995 | Chevrolet | C1500 | Cheyenne, Silverado |
| 1988 - 1992 | Chevrolet | C1500 | Scottsdale |
| 1990 - 1995 | Chevrolet | C1500 | WT |
| 1992 - 1995 | Chevrolet | C1500 Suburban | Base |
| 1995 | Chevrolet | C1500 Suburban | LT, LS |
| 1992 - 1994 | Chevrolet | C1500 Suburban | Silverado |
| 1993 | Chevrolet | C2500 | 400 SS, Custom |
| 1988 - 1995 | Chevrolet | C2500 | Base, Cheyenne, Silverado |
| 1988 - 1992 | Chevrolet | C2500 | Scottsdale |
| 1994 - 1995 | Chevrolet | C2500 | WT |
| 1992 - 1995 | Chevrolet | C2500 Suburban | Base |
| 1995 | Chevrolet | C2500 Suburban | LS, LT |
| 1992 - 1994 | Chevrolet | C2500 Suburban | Silverado |
| 1994 - 1995 | Chevrolet | C3500 | Base |
| 1988 - 1992 | Chevrolet | C3500 | Scottsdale |
| 1988 - 1995 | Chevrolet | C3500 | Silverado, Cheyenne |
| 1988 | Chevrolet | Camaro | Base |
| 1987 - 1990 | Chevrolet | Camaro | Iroc-Z |
| 1987 | Chevrolet | Camaro | LT, Sport |
| 1989 - 1992 | Chevrolet | Camaro | RS |
| 1987 - 1992 | Chevrolet | Camaro | Z28 |
| 1992 | Chevrolet | Camaro | Z28 Heritage Edition, RS Heritage Edition |
| 1987 - 1992 | Chevrolet | Caprice | Base |
| 1987 - 1993 | Chevrolet | Caprice | Classic |
| 1993 | Chevrolet | Caprice | Classic LS |
| 1987 - 1990 | Chevrolet | Caprice | Classic LS Brougham, Classic Brougham |
| 1991 - 1993 | Chevrolet | Caprice | Classic LTZ |
| 1991 - 1994 | Chevrolet | Commercial Chassis | Base |
| 1988 | Chevrolet | Corvette | 35th Anniversary Edition |
| 1987 - 1991 | Chevrolet | Corvette | Base |
| 1990 - 1991 | Chevrolet | Corvette | ZR-1 |
| 1987 | Chevrolet | El Camino | SS, Base |
| 1998 | Chevrolet | Express 1500 | LS, Base |
| 1996 | Chevrolet | Express 2500 | LS, Base |
| 1998 | Chevrolet | Express 3500 | LS, Base |
| 1987 | Chevrolet | G10 | Bonaventure |
| 1987 - 1995 | Chevrolet | G10 | Chevy Van, Beauville, Sportvan |
| 1995 | Chevrolet | G20 | Base |
| 1987 - 1995 | Chevrolet | G20 | Beauville, Chevy Van, Sportvan |
| 1987 - 1996 | Chevrolet | G30 | Hi-Cube, Sportvan, Beauville, Chevy Van |
| 1994 - 1995 | Chevrolet | K1500 | Base |
| 1988 - 1995 | Chevrolet | K1500 | Cheyenne, Silverado |
| 1988 - 1992 | Chevrolet | K1500 | Scottsdale |
| 1991 | Chevrolet | K1500 | Sport |
| 1990 - 1995 | Chevrolet | K1500 | WT |
| 1992 - 1995 | Chevrolet | K1500 Suburban | Base |
| 1995 | Chevrolet | K1500 Suburban | LT, LS |
| 1992 - 1994 | Chevrolet | K1500 Suburban | Silverado |
| 1988 - 1992 | Chevrolet | K2500 | Scottsdale |
| 1988 - 1995 | Chevrolet | K2500 | Silverado, Cheyenne |
| 1994 - 1995 | Chevrolet | K2500 | WT, Base |
| 1992 - 1995 | Chevrolet | K2500 Suburban | Base |
| 1995 | Chevrolet | K2500 Suburban | LT, LS |
| 1992 - 1994 | Chevrolet | K2500 Suburban | Silverado |
| 1994 - 1995 | Chevrolet | K3500 | Base |
| 1988 - 1995 | Chevrolet | K3500 | Cheyenne, Silverado |
| 1988 - 1992 | Chevrolet | K3500 | Scottsdale |
| 1987 - 1988 | Chevrolet | Monte Carlo | Base, LS, SS |
| 1987 - 1989 | Chevrolet | P20 | Base, Step-Van |
| 1987 - 1998 | Chevrolet | P30 | Base |
| 1987 - 1990 | Chevrolet | P30 | Step-Van |
| 1987 | Chevrolet | R10 | Scottsdale, Custom Deluxe, Silverado |
| 1987 | Chevrolet | R10 Suburban | Custom Deluxe |
| 1987 - 1988 | Chevrolet | R10 Suburban | Scottsdale, Silverado |
| 1989 - 1991 | Chevrolet | R1500 Suburban | Scottsdale, Silverado |
| 1988 | Chevrolet | R20 | Cheyenne |
| 1987 - 1988 | Chevrolet | R20 | Custom Deluxe, Scottsdale, Silverado |
| 1987 | Chevrolet | R20 Suburban | Custom Deluxe |
| 1987 - 1988 | Chevrolet | R20 Suburban | Scottsdale, Silverado |
| 1989 - 1991 | Chevrolet | R2500 Suburban | Silverado, Scottsdale |
| 1988 | Chevrolet | R30 | Cheyenne |
| 1987 - 1988 | Chevrolet | R30 | Custom Deluxe, Silverado, Scottsdale |
| 1989 - 1990 | Chevrolet | R3500 | Scottsdale |
| 1989 - 1991 | Chevrolet | R3500 | Silverado, Cheyenne |
| 1995 | Chevrolet | Tahoe | LS, Base, LT |
| 1987 | Chevrolet | V10 | Scottsdale, Silverado, Custom Deluxe |
| 1987 | Chevrolet | V10 Suburban | Custom Deluxe |
| 1987 - 1988 | Chevrolet | V10 Suburban | Silverado, Scottsdale |
| 1989 - 1991 | Chevrolet | V1500 Suburban | Scottsdale, Silverado |
| 1987 | Chevrolet | V20 | Silverado, Custom Deluxe, Scottsdale |
| 1987 | Chevrolet | V20 Suburban | Custom Deluxe |
| 1987 - 1988 | Chevrolet | V20 Suburban | Scottsdale, Silverado |
| 1989 - 1991 | Chevrolet | V2500 Suburban | Scottsdale, Silverado |
| 1988 | Chevrolet | V30 | Cheyenne |
| 1987 - 1988 | Chevrolet | V30 | Custom Deluxe, Scottsdale, Silverado |
| 1989 - 1990 | Chevrolet | V3500 | Scottsdale |
| 1989 - 1991 | Chevrolet | V3500 | Silverado, Cheyenne |
| 1993 | Excalibur | Limited | Base |
| 1987 - 1989 | Excalibur | Phaeton | Base |
| 1988 - 1995 | GMC | C1500 | Sierra SLE |
| 1988 - 1993 | GMC | C1500 | Sierra SLX, Sierra |
| 1994 - 1995 | GMC | C1500 | Sierra Special, Sierra SLT, Sierra SL |
| 1992 - 1995 | GMC | C1500 Suburban | SLE, Base |
| 1995 | GMC | C1500 Suburban | SLT |
| 1994 - 1995 | GMC | C2500 | Sierra SL, Sierra SLT |
| 1988 - 1995 | GMC | C2500 | Sierra SLE |
| 1988 - 1993 | GMC | C2500 | Sierra, Sierra SLX |
| 1992 - 1995 | GMC | C2500 Suburban | Base, SLE |
| 1995 | GMC | C2500 Suburban | SLT |
| 1994 - 1995 | GMC | C3500 | Sierra SL, Sierra SLT |
| 1988 - 1995 | GMC | C3500 | Sierra SLE |
| 1988 - 1993 | GMC | C3500 | Sierra, Sierra SLX |
| 1987 | GMC | Caballero | Base, Diablo |
| 1987 - 1995 | GMC | G1500 | Vandura, Rally, Rally STX |
| 1987 - 1995 | GMC | G2500 | Vandura, Rally STX, Rally |
| 1987 - 1988 | GMC | G3500 | Rally Custom |
| 1987 - 1996 | GMC | G3500 | Rally STX, Magnavan, Rally Camper Special, Rally, Vandura, Vandura Special |
| 1987 - 1991 | GMC | Jimmy | Base |
| 1987 - 1990 | GMC | Jimmy | Sierra Classic |
| 1988 - 1995 | GMC | K1500 | Sierra SLE |
| 1995 | GMC | K1500 | Sierra SLS |
| 1994 - 1995 | GMC | K1500 | Sierra Special, Sierra SLT, Sierra SL |
| 1993 | GMC | K1500 | Sierra Sport |
| 1988 - 1993 | GMC | K1500 | Sierra, Sierra SLX |
| 1992 - 1995 | GMC | K1500 Suburban | Base, SLE |
| 1995 | GMC | K1500 Suburban | SLT |
| 1988 - 1995 | GMC | K2500 | Sierra SLE |
| 1994 - 1995 | GMC | K2500 | Sierra SLT, Sierra SL |
| 1988 - 1993 | GMC | K2500 | Sierra, Sierra SLX |
| 1992 - 1995 | GMC | K2500 Suburban | Base, SLE |
| 1995 | GMC | K2500 Suburban | SLT |
| 1988 - 1995 | GMC | K3500 | Sierra SLE |
| 1994 - 1995 | GMC | K3500 | Sierra SLT, Sierra SL |
| 1988 - 1993 | GMC | K3500 | Sierra, Sierra SLX |
| 1987 - 1989 | GMC | P2500 | Value Van, Base |
| 1987 - 1996 | GMC | P3500 | Base |
| 1987 - 1990 | GMC | P3500 | Value Van |
| 1987 | GMC | R1500 | High Sierra, Sierra Classic, Base |
| 1987 - 1991 | GMC | R1500 Suburban | Base |
| 1987 | GMC | R1500 Suburban | High Sierra |
| 1987 - 1989 | GMC | R1500 Suburban | Sierra Classic |
| 1990 | GMC | R1500 Suburban | SLE |
| 1987 - 1989 | GMC | R2500 | Sierra Classic, High Sierra, Base |
| 1987 - 1991 | GMC | R2500 Suburban | Base |
| 1987 | GMC | R2500 Suburban | High Sierra |
| 1987 - 1989 | GMC | R2500 Suburban | Sierra Classic |
| 1990 | GMC | R2500 Suburban | SLE |
| 1987 - 1991 | GMC | R3500 | Base |
| 1987 - 1989 | GMC | R3500 | High Sierra, Sierra Classic |
| 1990 - 1991 | GMC | R3500 | SLE |
| 1987 | GMC | V1500 | Base, High Sierra, Sierra Classic |
| 1987 - 1991 | GMC | V1500 Suburban | Base |
| 1987 | GMC | V1500 Suburban | High Sierra |
| 1987 - 1989 | GMC | V1500 Suburban | Sierra Classic |
| 1990 | GMC | V1500 Suburban | SLE |
| 1987 | GMC | V2500 | High Sierra, Base, Sierra Classic |
| 1987 - 1991 | GMC | V2500 Suburban | Base |
| 1987 | GMC | V2500 Suburban | High Sierra |
| 1987 - 1989 | GMC | V2500 Suburban | Sierra Classic |
| 1990 | GMC | V2500 Suburban | SLE |
| 1987 - 1991 | GMC | V3500 | Base |
| 1987 - 1989 | GMC | V3500 | High Sierra, Sierra Classic |
| 1990 - 1991 | GMC | V3500 | SLE |
| 1993 | GMC | Yukon | GT |
| 1992 - 1995 | GMC | Yukon | SLE, Base |
| 1995 | GMC | Yukon | SLT |
| 1992 - 1994 | GMC | Yukon | Sport |
| 1991 - 1992 | Oldsmobile | Custom Cruiser | Base |
| 1987 - 1992 | Pontiac | Firebird | Base, Trans Am |
| 1989 - 1992 | Pontiac | Firebird | Formula, Trans Am GTA |
| 1989 | Pontiac | Firebird | Trans Am GTA SE |
| 1987 | Pontiac | Grand Prix | Brougham, LE, Base |